Perimeter of shapes

The perimeter of a figure is the distance around the outside of the figure. This is true whether the figure is a familiar figure like a rectangle or triangle, or if it is a complex figure like the floorplan of a house.

To find the perimeter of this figure, you need to add the lengths of all 6 sides.

Perimeter = 5 + 3 + 3 + 1 + 2 + 2 = 16 units

Since a rectangle has four sides with opposite sides being congruent, the formula for finding the perimeter is Side A + Side B + Side A + Side B. This could also be stated as $$\mbox{2•Side A + 2•Side B}$$ or $$\mbox{2•(Side A + Side B)}$$

To find the perimeter of a 4-by-6 rectangle you need to add the lengths of the four sides of the rectangle.